Electronic systems, such as computer systems, rely for proper operation on the transmission of electronic signals among the various components of the system. In a computer system, for example, electronic signals must be transmitted from the computer to a keyboard, a video monitor, a mouse, and any other peripheral electronic devices coupled to the computer. The acronym KVM will be used herein to mean “keyboard, video monitor, and mouse,” following a practice that is standard in the art. Additionally, the phrase “peripheral device” will be used herein to mean any electronic device coupled to a computer or forming a part of any electronic system, including a keyboard, a video monitor, and a mouse.
Under certain circumstances it may be desirable to place the computer in one location and to place the peripheral devices in another location separated from the computer's location by a certain distance. An example of such a circumstance is where the computer must be in an environment, perhaps a particular room in a building, where parameters such as access, temperature, humidity, and the like are carefully controlled but where the peripheral devices may be located in an environment, perhaps another room in the building, where control over such parameters is less critical. Another example of such a circumstance is where a single keyboard, video monitor, and mouse, referred to collectively herein as an “operator control center” or an “OCC,” are adapted to control several computers, where the several computers may be located at a distance from the operator control center.
KVM extenders have been developed in order to increase the distance by which an operator control center can be separated from a computer. Existing KVM extenders include a local subsystem, a remote subsystem, and a cable coupled between the local and remote subsystems. The local subsystem is coupled to a computer and/or, if applicable, to a KVM Switch that switches control from one to another of several computers being controlled by an operator control center. The remote subsystem is coupled to the OCC. Electronic signals may be transmitted between the computer and the OCC across the cable via the local and remote subsystems.
Both the local and remote subsystems of existing KVM extenders require the use of power supplies, alternating current (AC) adapters, or the like to provide power to the subsystems. Such power supplies, AC adapters, and the like are bulky and take up a significant amount of space. In many environments, such as in a server rack or in an environmentally controlled room, space is at a premium, and the presence of a power supply or an AC adapter is an inefficient use of that space. Accordingly, there exists a need for a KVM extender providing all of the functionality of existing KVM extenders but that does not require a separate power supply or AC adapter.
For simplicity and clarity of illustration, the drawing figures illustrate the general manner of construction, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the invention. Additionally, elements in the drawing figures are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of embodiments of the present invention. The same reference numerals in different figures denote the same elements.
The terms “first,” “second,” “third,” “fourth,” and the like in the description and in the claims, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms “comprise,” “include,” “have,” and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
The terms “left,” “right,” “front,” “back,” “top,” “bottom,” “over,” “under,”and the like in the description and in the claims, if any, are used for descriptive purposes and not necessarily for describing permanent relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein. The term “coupled,” as used herein, is defined as directly or indirectly connected in an electrical, mechanical, or other manner.